Suspension device

ABSTRACT

A suspension device according to one embodiment of the present disclosure is equipped with: an upper arm; a lower arm; a leaf spring positioned so as to extend in the vehicle widthwise direction in a manner such that an end section thereof is provided on the lower arm; a first bracket configured in a manner such that a shock absorber connected to the lower arm is connected to the outside of a side member in the vehicle widthwise direction; an upper bushing capable of transmitting force between the leaf spring and a suspension cross member; and a second bracket which is independent from the first bracket and is positioned below the side member between the side member and the leaf spring so as to be capable of transmitting the elastic force of the leaf spring to the side member via the upper bushing.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a U.S. National Stage entry of PCT Application. No.PC/JP2018/044636 filed on Dec. 5, 2018, which claims priority to JPApplication No. 2017-236359, filed on Dec. 8, 2017. The contents of theforegoing are incorporated by reference.

TECHNICAL FIELD

The present disclosure relates to a suspension device of an independentsuspension type for a vehicle.

BACKGROUND ART

In a vehicle, a suspension device of a double wishbone type, which isone of independent suspension types for wheels, has been used in therelated art. This kind of suspension device includes an upper arm thatis swingably supported, by a side member of a vehicle body frame, arounda support shaft, and a lower arm that is swingably supported, by asuspension cross member on the vehicle body side, around a supportshaft. The upper arm and the lower arm are connected to a knuckle of awheel.

Patent Literature 1 discloses an example of such a suspension device.The suspension device of Patent Literature 1 includes the upper arm andthe lower arm that are connected to a knuckle via a ball joint. Further,the suspension device includes a coil spring provided between the lowerarm and a spring receiver fixed to the vehicle body frame, a shockabsorber extending to a center of the coil spring, and a leaf springdisposed laterally in a vehicle width direction and having both endsconnected to corresponding lower arms.

CITATION LIST Patent Literature

-   Patent Literature 1: JP-A-H7-112607

SUMMARY OF INVENTION Technical Problem

It is conceivable to carry out various improvements in the suspensiondevice of Patent Literature 1. For example, it is conceivable toincrease a degree of freedom in design by attempting to improverelationships between various constituent elements. However, even ifsuch improvements are achieved, it is necessary to avoid a significantdecrease in the strength (rigidity) of the suspension device and to havesufficient rigidity against an input (for example, vibration) from awheel side.

An object of the technology of the present disclosure is to provide asuspension device excellent in rigidity.

Solution to Problem

To achieve the above object, a technology of the present disclosureprovides a suspension device including: an upper arm configured toswingably support a knuckle of a wheel, the upper arm being configuredto be swingably supported by a side member extending in a vehiclefront-rear direction; a lower arm configured to swingably support theknuckle, the lower arm being configured to be swingably supported by asuspension cross member extending in a vehicle width direction; a shockabsorbing device disposed between the lower arm and the side member, aleaf spring extending in the vehicle width direction, the leaf springhaving an end portion disposed on the lower arm; a first bracketconfigured such that the shock absorbing device is connected to an outerside of the side member in the vehicle width direction; a transmissionunit provided between the suspension cross member and the leaf spring,the transmission unit being configured to transmit a force between theleaf spring and the suspension cross member and a second bracketdisposed between the leaf spring and the side member and on a verticallylower side of the side member, the second bracket being configured totransmit an elastic force of the leaf spring to the side member via thetransmission unit, the second bracket being independent of the firstbracket (the second bracket being configured as a separate component).

Preferably, the leaf spring passes through an inside of a main crossmember of the suspension cross member, the transmission unit is providedinside the main cross member, and the second bracket has a connectionregion with the main cross member, the connection region being locatedon an inner side of the side member in the vehicle width direction.

When the suspension cross member includes: the main cross memberextending in the vehicle width direction; a sub-cross member extendingin the vehicle width direction; and a vertical member extending in thevehicle front-rear direction to connect the main cross member to thesub-cross member, the second bracket is provided between the main crossmember and the vertical member.

Advantageous Effects of Invention

The suspension device according to the technology of the presentdisclosure can have excellent rigidity since the suspension device hasthe above configuration.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a configuration view of a suspension device according to anembodiment of a technology of the present disclosure, and is a view seenfrom a side of a vehicle.

FIG. 2 is a configuration view of the suspension device of FIG. 1 on onewheel side, and is a partial cross-sectional view.

FIG. 3 is a view illustrating a lower arm and a leaf spring of thesuspension device of FIG. 1.

FIG. 4 is a diagram showing assembly in a suspension device according tothe related art.

FIG. 5 is a diagram showing assembly in the suspension device of FIG. 1.

FIG. 6 is a schematic diagram showing the suspension device of FIG. 2.

DESCRIPTION OF EMBODIMENTS

An embodiment of the present disclosure will be described below withreference to the accompanying drawings. The same components (orconfigurations) are denoted by the same reference numerals, and namesand functions thereof are also the same. Therefore, detaileddescriptions of the same components are not repeated.

FIG. 1 illustrates a schematic configuration of a part of a suspensiondevice 10 according to an embodiment of a technology of the presentdisclosure. FIG. 2 illustrates a configuration of the suspension device10 on one wheel side, and a part thereof is illustrated in crosssection. Here, the suspension device 10 is applied to a front wheel of avehicle, and a reference numeral “12” in FIG. 2 indicates a hub thatsupports a left front wheel (not illustrated). FIG. 1 is a view, seenfrom a lateral side of the left front wheel, of the suspension device 10in FIG. 2 (illustrating with the hub and a knuckle of the left frontwheel excluded). A right front wheel side (not illustrated) hassubstantially a configuration that is bilaterally symmetric with theconfiguration of FIGS. 1 and 2, so that descriptions thereof will besubstantially omitted below. A vehicle width direction is a directionsubstantially perpendicular to a paper plane in FIG. 1 and is adirection substantially parallel to a paper plane in FIG. 2, and avehicle front-rear direction is a direction substantially parallel tothe paper plane in FIG. 1 and is a direction substantially perpendicularto the paper plane in FIG. 2.

The suspension device 10 is configured as a suspension device of anindependent suspension type. The suspension device 10 includes an upperarm 14 having a substantial V shape or a substantial A shape in a planview, and a lower arm 16 having a substantial V shape or a substantial Ashape in a plan view. An upper part of a knuckle 18 of a wheel ispivotally supported, that is, swingably supported via a ball joint 20 bythe upper arm 14, particularly by an outer end portion (base portion) 14a of the upper arm 14 in the vehicle width direction. A lower part ofthe knuckle 18 of the wheel is swingably supported via a ball joint 22by the lower arm 16, particularly by an outer end portion (base portion)16 a of the lower arm 16 in the vehicle width direction.

An arm end portion 14 c of each of two arm portions 14 b, which arebifurcated inward in the vehicle width direction from the base portion14 a of the upper arm 14, is connected to an upper arm bracket 25 a of abracket 24. Thus, the upper arm 14 is swingably supported around asupport shaft of the brackets 25 a. The bracket 24 is fixed to a sidemember 26 extending in the vehicle front-rear direction. The sidemembers 26 are constituent elements of a vehicle body frame BF (notillustrated), and are disposed on both sides of the vehicle. In thesuspension device 10, as illustrated in FIG. 1, the bracket 24 is fixedto the side member 26 by five bolts B arranged in a W shape. However,the number, arrangement, and the like of the bolts for fixing thebracket 24 are not limited to this example.

A suspension cross member 28 is disposed, in the vehicle widthdirection, on a vertically lower side of, that is, below the left andright side members 26 of the vehicle body frame BF (FIGS. 1 and 2illustrate only the side member 26 on the left side of the vehicle). Thesuspension cross member 28 has a certain width in the vehicle front-reardirection and includes a plurality of members extending in the vehiclewidth direction and a plurality of members extending in the vehiclefront-rear direction that connect these above members. Specifically, thesuspension cross member 28 includes a main cross member 30 extending inthe vehicle width direction, a sub-cross member 32 extending in thevehicle width direction, and a vertical member 34 extending in thevehicle front-rear direction. Here, the sub-cross member 32 is separatedfrom the main cross member 30 and is disposed substantially parallel tothe main cross member 30 on a vehicle front side of the main crossmember 30. The vertical member 34 is provided across the main crossmember 30 and the sub-cross member 32. Here, constituent elements of thesuspension cross member are generally formed of steel materials and areintegrated by welding, but the materials and joining methods are notlimited to this example. In addition, as for such a configuration of thesuspension cross member 28, a configuration that the suspension crossmember only includes a main cross member is not excluded in the presentdisclosure. As illustrated in FIGS. 1 and 2, in the suspension device10, the vertical member 34 comes into contact with the side member 26when the suspension cross member 28 is attached and fixed to the sidemember 26. In addition, the main cross member 30 and the sub-crossmember 32 support a steering gear box SU therebetween.

More specifically, the main cross member 30 is attached to the verticalmember 34 via a bracket 36. The bracket 36 is attached to an upperportion of the main cross member of the suspension cross member 28. Thebracket 36 covers the main cross member 30 from above as illustrated inFIG. 1, and is provided on the upper portion of the main cross member 30relative to an end portion (in the vehicle width direction) of the maincross member 30 as illustrated in FIG. 2. As illustrated in FIGS. 1 and2, the vertical member 34 straddles an upper portion of the bracket 36.In this way, in the suspension device 10, the bracket 36 is incorporatedinto the suspension cross member 28. However, the bracket 36 may beattached to an outer portion of the suspension cross member 28 (that is,the suspension cross member 28 may be attached to the side member 26 viathe bracket 36). In any of these aspects, the suspension cross member 28is connected to the vertically lower side of the vehicle body frame BF(side member 26), and at this time, the bracket 36 is located in thesuspension cross member 28 or on an upper side of the suspension crossmember 28. Hereinafter, in order to distinguish the bracket 36 from thebracket 24, the bracket 24 is referred to as an upper bracket, and thebracket 36 is referred to as a lower bracket. The upper bracket 24corresponds to a first bracket in the technology of the presentdisclosure, and the lower bracket 36 corresponds to a second bracket inthe technology of the present disclosure.

The sub-cross member 32 is also attached to the vertical member 34 via asupport bracket 33. A lower end portion of the support bracket 33extending in a substantially vertical direction (substantiallyupper-lower direction) is joined to each of both end portions of thesub-cross member 32 in the vehicle width direction so as to cover thesub-cross member 32 from above. In this way, an upper end portion of thesupport bracket 33 joined to the sub-cross member 32 is joined to thevertical member 34, so that the sub-cross member 32 is attached to thevertical member 34.

The suspension cross member 28 further includes lower arm brackets 38.An arm end portion 16 c of each of two arm portions 16 b that bifurcateinward in the vehicle width direction from the base portion 16 a of thelower arm 16 is connected to the lower arm bracket 38. Thus, the lowerarm 16 is swingably supported around a support shaft of the brackets 38.Here, as illustrated in FIG. 1, the lower arm brackets 38 sandwich themain cross member 30 in the vehicle front-rear direction. Here, thelower arm bracket 38 on the vehicle front side is also configured as thesupport bracket 33 joined to the outer end portion of the sub-crossmember 32 in the vehicle width direction. Therefore, the lower armbracket 38 on the vehicle front side serves as the support bracket 33.The lower arm bracket 38 on the vehicle rear side is connected to anextension portion 30E of the main cross member 30, and an upper end sideof the lower arm bracket 38 is attached and fixed to the vertical member34. Thus, the lower arm 16 is not directly connected to the lowerbracket 36, and the lower bracket 36 is separated from the lower arm 16.

In the suspension device 10, a leaf spring 40 is disposed horizontallyso as to extend in the vehicle width direction. The leaf spring 40passes through an inner cavity 30 s of the main cross member 30 of thesuspension cross member 28. One end portion 40 a of the leaf spring 40is disposed on a support portion 44 of the lower arm 16 on a left frontwheel side (the hub 12 side in FIG. 2) as described below, and the otherend portion of the leaf spring 40 is similarly disposed on a supportportion 44 of the lower arm 16 on a right front wheel side (notillustrated).

The support portion 44 is formed on a vertically upper side of, that is,above a substantial triangular region formed between the base portion 16a of the lower arm 16 and the arm portion 16 b extending in thebifurcated manner from the base portion 16 a, such that the supportportion 44 is substantially horizontal in the vehicle. The leaf spring40 has a shape that generally extends in the vehicle width direction andis curved to slightly protrude upward in the vertical direction. Anintermediate part 40 b of the leaf spring 40 is accommodated in thesuspension cross member 28. More specifically, the intermediate part 40b is accommodated in the main cross member 30 of the suspension crossmember 28, and is supported, by a bushing member 47, with respect to themain cross member 30. Specifically, the intermediate part 40 b of theleaf spring 40 is supported, with respect to the main cross member 30,by the bushing member 47 on the left front wheel side (an upper bushing48 and a lower bushing 50), and a bushing member (not illustrated) onthe right front wheel side (an upper bushing and a lower bushing). Thebushing member 47 includes the upper bushing 48 located on a verticallyupper side of the leaf spring 40 and connected to an inner surface ofthe main cross member 30, and the lower bushing 50 located on avertically lower side of the leaf spring 40 and connected to an innersurface of the main cross member 30. The leaf spring is pressed againstthe support portion 44 of the lower arm 16 by the upper bushing 48. Theupper bushing 48 corresponds to a transmission unit that can transmit aforce from the leaf spring 40 to the suspension cross member 28. Thelower bushing 50 supports the leaf spring 40 so that the leaf spring 40can play various roles or functions, for example, play roles as astabilizer. By providing the lower bushing 50 as well, the leaf spring40 can be curved in a substantial S shape and can act on both the leftand right front wheels when different forces are generated at the leftand right front wheels, for example, when the left front wheel is liftedupward, but the right front wheel is lowered downward.

As illustrated in FIG. 3, the lower arm 16 includes the support portion44 and a lower arm cover portion 16 e covering an upper side of thesupport portion 44 in the vertical direction. In order to clarify thedistinction with the cover portion 16 e, a main body portion 16 d, whichincludes the base portion 16 a and the arm portions 16 b extending inthe bifurcated manner from the base portion 16 a as described above, maybe referred to as a lower arm main body portion.

In the lower arm 16, the lower arm main body portion 16 d is providedwith the support portion 44 for supporting the end portion of the leafspring 40. The support portion 44 is placed on the lower arm 16 and canbe detached or replaced with respect to the lower arm 16. Similar to thelower arm 16, the support portion 44 is formed of a steel material inthe metal materials. An elastic body 44 a is provided on a lower side ofthe support portion 44. The elastic body 44 a increases buffer capacitywhen a large force acts on the support portion 44, and further, absorbsa difference between a rotation trajectory of the lower arm 16 and arotation trajectory of the leaf spring 40. The lower arm 16, in whichthe cover portion 16 e is attached to the lower arm main body portion 16d, has an opening portion 16 f opening inward in the vehicle widthdirection. The leaf spring 40 extends in a space in the lower arm 16through the opening portion 16 f, and the end portion of the leaf spring40 is supported by the support portion 44 of the lower arm 16. Asdescribed above, the lower arm 16 has a space, but the cover portion 16e has a predetermined reinforcing shape so that the lower arm 16 hasstrength or rigidity equal to or greater than a predetermined level.Specifically, in the lower arm 16, the cover portion 16 e has asubstantial arch shape (substantial U shape) at the opening portion 16f. In FIGS. 1 and 2, the leaf spring 40 is separated from an innersurface of the cover portion 16 e.

A shock absorber 46, which is a shock absorbing device, extends betweenthe lower arm 16 and the side member 26 having the above configuration.One end portion 46 a of the shock absorber 46 is connected to the lowerarm 16. A connection portion 16 g of the lower arm 16 with respect tothe shock absorber 46 is provided on a vertically upper surface of thecover portion 16 e of the lower arm 16, and is located substantiallyabove a vicinity of the base portion 16 a of the lower arm 16. The otherend portion 46 b of the shock absorber 46 is connected to a connectionportion 25 b, between the two upper arm brackets 25 a, of the upperbracket 24.

In the suspension device 10 having the above configuration, as isapparent from the above descriptions and drawings, the upper bracket 24,which is connected to an outer side of the side member 26 in the vehiclewidth direction is independent of and separated from the suspensioncross member 28 connected to the vertically lower side of the sidemember 26. In contrast, in a suspension device according to the relatedart, a bracket connecting a suspension cross member to a side memberextends to the outside of the side member 26 in the vehicle widthdirection. For example, in a suspension device of Patent Literature 1, abracket connecting the suspension cross member to the side member coversa periphery of a coil spring extending around the shock absorber, and isintegrated with a spring receiver. Therefore, in the suspension deviceof Patent Literature 1, a design relationship between constituentmembers is very strong. Since the suspension device 10 has the aboveconfiguration, the suspension device 10 has a high degree of freedom indesign as compared with such a suspension device according to therelated art. The upper bracket 24 is independent of the lower bracket 36covering the end portion of the main cross member 30 from above andlocated on a vertically lower side of, that is, below the side member26. Thus, the upper arm 14 and the shock absorber 46, which areconnected to the upper bracket 24, are not directly connected to thelower bracket 36, that is, in a disconnected state. Therefore, thesuspension device 10 has a higher degree of freedom in design. Asdescribed above, the suspension device 10 has a configuration in whichthe upper bracket 24 and the lower bracket 36 are independent of eachother (a configuration having separate components).

Since the suspension device 10 has a configuration in which the upperbracket 24 and the lower bracket 36 are independent of each other, thesuspension device 10 is excellent in the assemblability of the vehiclebody frame BF. Here, a suspension device according to the related artwill be described first. FIG. 4 schematically shows a vehicle body frameBF including left and right side members 26, and a suspension crossmember 28′ including brackets B having a substantially L-shaped crosssection as the bracket described in Patent Literature 1. As can be seenfrom FIG. 4, in the suspension device according to the related art, whenthe suspension cross member 28′ including the brackets B is assembledwith the vehicle body frame BF, precise positioning, between thesuspension cross member 28′ and the vehicle body frame BF, in the front,the rear, the left, and the right, and a horizontal direction isrequired.

In contrast, in the suspension device 10 according to the presentembodiment, the upper bracket 24 and the lower bracket 36 (that is, thesuspension cross member 28) are separated from and independent of eachother as described above. That is, the upper bracket 24 is not fixed tothe suspension cross member 28 and is independent of and separated fromthe suspension cross member 28. With this configuration, the upperbracket 24 may be attached to the side member 26 separately from thesuspension cross member, and the suspension cross member 28 includingthe lower bracket 36 may be attached to the side member 26 separatelyfrom the upper bracket 24. The upper arm 14 and the shock absorber 46are attached to the upper bracket 24. Then, the suspension cross member28 including the lower bracket 36 is assembled. Although the upperbracket 24 and the suspension cross member 28 are connected via theshock absorber 46 and the lower arm 16, positions of the upper bracket24 and the suspension cross member 28 are not determined fixedly. Thisis readily understood from the fact that the lower arm 16 is swingablyattached to the suspension cross member 28 and the end portion 46 a ofthe shock absorber 46 is rotatable (swingable) around a support shaft.Therefore, as schematically shown in FIG. 5, when the suspension crossmember 28 is attached to the vehicle body frame BF, rough positioning ofthe suspension cross member 28 and the vehicle body frame BF, in thefront, the rear, the left, and the right, and a horizontal direction isperformed without a need for the precise positioning in the suspensiondevice according to the related art, so that the suspension cross member28 and the vehicle body frame BF are in contact with each other, andthen the positional relationship can be finely adjusted. In a statewhere the suspension cross member 28 is fixed to the vehicle body frameBF (in particular, the side member 26) together with the lower bracket36, the upper bracket 24 can be firmly fixed to the side member 26. Inthis way, by adopting the above configuration in which the upper bracket24 and the lower bracket 36 (that is, the suspension cross member 28)are independent of and separated from each other, it is possible toimprove the assemblability of the constituent elements, particularly thesuspension cross member 28, to the vehicle body frame BF (mainly theside member 26) in the suspension device 10.

The suspension device 10 includes a bump rubber 52 provided on the lowerbracket 36 so as to increase shock resistance and the like of thesuspension device 10. Further, the suspension device 10 is excellent inthe strength or the rigidity as described below with reference to FIGS.2 and 6. FIG. 6 is a schematic diagram of the suspension device of FIG.2.

First, as described above, one end portion 46 a of the shock absorber 46is connected to the lower arm 16, and the other end portion 46 b of theshock absorber 46 is connected to the upper bracket 24. In the vehiclewidth direction, the connection portion of the shock absorber 46 to thelower arm 16 is outside the upper bracket 24. Then, the upper bracket 24is connected to the side member 26 from the outside in the vehicle widthdirection. Therefore, the shock absorber 46 can exert a force to theside member 26 from the outside to the inside of the vehicle in thevehicle width direction. In this way, a first transmission route of theforce from the outside in the vehicle width direction to the side member26 is formed.

A second transmission route of a force, which is different from thefirst transmission route of the force from the outside in the vehiclewidth direction to the side member 26, is formed on the vertically lowerside of the side member 26. In the second transmission route, the upperbushing 48 and the lower bracket 36 that is independent of the upperbracket 24 are provided. In the second transmission route, the forcefrom the leaf spring 40 can be applied to the side member 26 via theupper bushing 48, the main cross member 30, the lower bracket 36, andthe vertical member 34 in this order.

In the suspension device 10, for example, when a force F to lift the hub12 upward in the vertical direction acts on the wheel, a moment M1 fromthe outside of the vehicle to the inside of the vehicle as schematicallyshown in FIG. 6 may act on the side member 26 via the lower arm 16 andthe shock absorber 46 in the first transmission route. On the otherhand, when the force F acts on the wheel (the hub 12), a force istransmitted from the lower arm 16 to the leaf spring 40, and then aforce from the leaf spring, that is, an elastic force is transmitted tothe main cross member 30 via the upper bushing 48. As a result, sincethe lower bracket 36 (independent of the upper bracket) is disposed onthe vertically lower side of the side member 26, a moment M2 from theinside of the vehicle to the outside of the vehicle as schematicallyshown in FIG. 6 can act on the side member 26. As can be seen from FIG.6, these moments M1 and M2 are forces in directions in which the momentsM1 and M2 cancel each other out. That is, when the force F acts on thewheel (the hub 12), only a moment corresponding to the moment M1 acts onthe side member 26 in the suspension device of Patent Literature 1,whereas the moments M1 and M2 in directions in which the moments M1 andM2 cancel each other out can act on the side member 26 in the suspensiondevice 10 of the present embodiment. Therefore, the suspension device 10of the present embodiment does not require a structural changeaccompanied by weight increase, for example, increasing a thickness ofthe side member, and is excellent in the rigidity with respect to theforce F.

In the suspension device 10, the lower bracket 36 substantially has aconnection region with the main cross member 30 on the inside of thevehicle relative to the side member 26 in the vehicle width direction(see FIGS. 2 and 6). The connection region extends to the verticallyupper side of the upper bushing 48 (which is located inward than theside member 26 in the vehicle width direction). Therefore, as shown inFIGS. 2 and 6, the lower bracket is formed such that a vertically upperpart of the lower bracket 36 is located outward than a vertically lowerpart of the lower bracket 36 in the vehicle width direction. Therefore,when the force F acts on the wheel, the lower bracket 36 can apply anupward force, which is transmitted from the leaf spring 40 via the maincross member 30, to the side member 26 more suitably, and whereby themoment M2 can be generated. In this way, the lower bracket 36 mayfunction as a force transmission member that transmits a force betweenthe leaf spring 40 and the side member 26 via the main cross member 30,the upper bushing 48, or the like.

The present disclosure is not limited to the above-described embodiment,and may be appropriately modified and implemented without departing fromthe scope of the present disclosure.

For example, in the above embodiment, the upper arm and the shockabsorber are connected to a single upper bracket 24. However, the upperbracket 24 is not limited to being a single member, and may include twoor more members. For example, the upper bracket 24 may include twoseparated upper arm brackets for connecting the upper arm, and a bracketfor connecting the shock absorber, which is provided between the twoseparated upper arm brackets. These three brackets may be completelyseparate and independent, and are preferably integrally formed orintegrated together.

Each constituent element of the technology of the present disclosure maybe formed of various materials (which are not limited to being formed ofa material as described above). For example, the support portion 44 isnot limited to being formed of a steel material, and may be formed ofother materials such as a non-ferrous metal material and a resinmaterial. The support portion 44 may be formed of a material differentfrom that of the lower arm.

The technology of the present disclosure is not limited to being appliedto a front wheel of a vehicle, and may be applied to a rear wheel.

The present application is based on a Japanese Patent Application(Japanese Patent Application No. 2017-236359), filed on Dec. 8, 2017,the contents of which are incorporated herein by reference.

INDUSTRIAL APPLICABILITY

The present disclosure has an effect of being able to provide asuspension device having excellent rigidity, and is useful to contributeto the realization of a vehicle excellent in safety and travelingperformances.

REFERENCE SIGN LIST

-   -   10 Suspension device    -   14 Upper arm    -   16 Lower arm    -   18 Knuckle    -   24 Upper bracket (first bracket)    -   26 Side member    -   28 Suspension cross member    -   30 Main cross member    -   32 Sub-cross member    -   34 Vertical member    -   36 Lower bracket (second bracket)    -   40 Leaf spring    -   46 Shock absorber (shock absorbing device)    -   47 Bushing member    -   48 Upper bushing    -   50 Lower bushing

The invention claimed is:
 1. A suspension device comprising: an upperarm configured to swingably support a knuckle of a wheel, the upper armbeing configured tip be swingably supported by a side member extendingin a vehicle front-rear direction; a lower arm configured to swingablysupport the knuckle, the lower arm being configured to be swingablysupported by a suspension cross member extending in a vehicle widthdirection; a shock absorbing device disposed between the lower arm andthe side member; a leaf spring extending in the vehicle width direction,the leaf spring having an end portion disposed on the lower arm; a firstbracket configured such that the shock absorbing device is connected toan outer side of the side member in the vehicle width direction; atransmission unit provided between the suspension cross member and theleaf spring, the transmission unit being configured to transmit a forcebetween the leaf spring and the suspension cross member; and a secondbracket disposed between the leaf spring and the side member and on avertically lower side of the side member, the second bracket beingconfigured to transmit an elastic force of the leaf spring to the sidemember via the transmission unit, wherein the second bracket is aseparate component from the first bracket.
 2. The suspension deviceaccording to claim 1, wherein the leaf spring passes through an insideof a main cross member of the suspension cross member, wherein thetransmissions unit is provided inside the main cross member, and whereinthe second bracket has a connection region with the main cross member,the connection region being located on an inner side of the side memberin the vehicle width direction.
 3. The suspension device according toclaim 1, wherein the suspension cross member includes: the main crossmember extending in the vehicle width direction: a sub-cross memberextending in the vehicle width direction; and a vertical memberextending in the vehicle front-rear direction to connect the main crossmember to the sub-cross member, and wherein the second bracket isprovided between the main cross member and the vertical member.